AWS Amplify branch environment variables

A branch's build and runtime read these. A write replaces the whole set, so a console edit made between our read and our write is lost.

The connection

What	This provider
Vendor	Amazon Web Services
Key	`aws-amplify-branch-env`
Availability	`available`. You can connect it today.
Credential penv holds	`aws-role`
Values read back	yes
Activation	`on-next-deploy`

Direction	What it does
`import`	Reads names and values out of the store into penv.
`export`	Writes names and values from penv into the store.

on-next-deploy. A new value waits there and arrives with your next deploy.

Direction	Policies you can pick
`import`	`skip_existing`, `new_version`, `fail`
`export`	`create_only`, `overwrite`, `overwrite_and_prune`

How syncs work says what each one does.

You grant penv access in your own AWS account. Pick one of these in the wizard.

penv generates the shared value the grant is conditioned on, so there is nothing for you to invent.

Review the grant in code, then paste the role ARN back. Apply a rendered policy or template. You paste the result back into the wizard.

Set aside about 10 minutes.

It gives you:

Name	Label	Kind	What it is
`snippet`	Terraform	read only, a block to copy
`externalId`	External ID	read only, filled in for you	Already baked into the snippet. Only Penv-cloud can assume the role with it.

You paste back:

Field	Label	Kind	Required	What it is
`roleArn`	Role ARN	text	yes	The ARN the grant printed. We assume it once to check it before saving.

Create the role manually from the two policies below. Paste a credential you already hold. You paste the result back into the wizard.

Set aside about 10 minutes.

It gives you:

Name	Label	Kind	What it is
`penvAccountId`	Penv-cloud AWS account ID	read only, filled in for you	The account the role trusts.
`roleName`	Suggested role name	read only, filled in for you	Unique to this attempt, so it cannot collide with a role another connection made.
`externalId`	External ID	read only, filled in for you	Required in the trust policy. Only Penv-cloud can assume the role with it.
`trustPolicy`	Trust policy	read only, a block to copy
`permissionsPolicy`	Permissions policy	read only, a block to copy

You paste back:

Field	Label	Kind	Required	What it is
`roleArn`	Role ARN	text	yes	The ARN the grant printed. We assume it once to check it before saving.

Fixed when you connect, and shared by every mapping on it.

Field	Label	Kind	Required	Advanced	What it is
`region`	Region	text	yes	no	The region this connection reaches. One connection covers one region.
`accountId`	Account ID	text	no	yes	If supplied, the generated policy names the account instead of a wildcard.
`appId`	App ID	text	yes	no	The Amplify app this connection may touch. The grant is scoped to it.
`roleArn`	Role ARN	read only, filled in for you	yes	no	The role we assume. Filled in by the grant you just completed.

Answered once per environment you map.

Field	Label	Kind	Required	Advanced	What it is
`branchName`	Branch	text	yes	no	The branch whose environment variables this maps onto.

penv probes for these when it verifies the connection.

Permission	Directions	Blocking	Without it
`sts:GetCallerIdentity`	every direction	yes	We cannot confirm which IAM identity this credential is.
`amplify:GetBranch`	every direction	yes	Preview cannot list the branch's variables.
`amplify:UpdateBranch`	`export`	yes	Export cannot write anything.